Systems and methods for electricity generation, storage, distribution, and dispatch

ABSTRACT

A property power system can include multiple photovoltaic (PV) panels to generate DC electrical energy from solar energy and a first power conversion module to convert between DC and AC electrical energy and to control aspects of each PV panel. The property power system can have a group of battery blades to store electrical energy and another power conversion module to convert between DC and AC electrical energy and to control aspects of each battery blade. The property power system can have a multiple synchronization interfaces configured to aggregate the AC electrical energy of each of the PV panels/battery blades, respectively, and to control delivery of the aggregated AC electrical energy. The property power system can include a grid circuit disconnector to prevent back-feed of power during grid outage condition while the PV panels or the group of battery blades is powering an electrical load center of the property.

CROSS REFERENCE TO RELATED APPLICATIONS

This claims priority to U.S. Provisional Application No. 62/732,685titled “Systems and Methods for Electricity Generation, Storage,Distribution, and Dispatch” and filed Sep. 18, 2019, the entirety ofwhich is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to systems and methods forgenerating, storing, distributing, and dispatching energy generated bymultiple energy sources such as a photovoltaic (PV) panel and a battery.In particular, systems for holistic integration of PV-battery systemsfor installation into particular locations are described.

BACKGROUND

With the higher proliferation of intermittent renewable generationresources, such as PV systems on power distribution networks,cost-effective grid management—voltage stabilization and frequencycontrol—is increasingly becoming a challenge. The transformation of theelectrical grid from traditional centralized power plants—primarilylocated on the bulk power system or network—to distributed powergeneration that can include substantial quantities of renewables on thedistribution system or network may involve significant quantities offlexible generation and storage. In order to fully derive the value ofrenewable generation, intermittent resources are supplemented with acombination of fast ramp capable generation resources and distributedenergy storage. This can be seen in the evolution of the so-called “duckcurve” that is shown in FIG. 1.

Fast ramping resources are typically: (1) centralized multi-hundredmegawatts (MW) combined cycle natural gas turbine-based power plants,also known as peaker plants; and (2) distributed energy storageconsisting of large scale storage (compressed air, liquefied air, flowbatteries, Li-Ion batteries) and customer-sited energy storage inresidential, light and large commercial buildings. While centralizedpower plants are on the bulk power system (high voltage network),customer-sited storage, also known as behind-the-meter (BTM) energystorage systems, on the distribution network, are usually more readilyavailable—from a situational perspective—and utilities are expected tobecome more reliant on BTM systems for managing their distributionnetworks with higher penetration of intermittent generation. BTM orcustomer sited systems are expected to be called upon to handle andmanage grid imbalances, voltage and frequency disturbances, for example,low voltage ride-through, frequency regulation for enhanced reliabilityand islanded or microgrid operation for system resiliency. Such systemscan also deliver additional reliability and resiliency to the nextgeneration, highly nimble grid.

While there exists a clear technical and business case for BTM storagesystems, from grid operators' perspectives, return-on-investmentassociated with stationary storage or battery energy storage system(BESS) for the home and property owners (end customer) is questionable.The installed costs of BTM storage systems or BESS remain exorbitantlyexpensive—varying from $700 to 2,500/kWh—negating any potential derivedvalue, from the homeowners' perspective, obtained from supplying gridservices. Presently, these systems are heavily subsidized byjurisdictions that are in the forefront of renewable energydeployment—like California's Self Generation Incentive Program and NewYork's Reforming the Energy Vision Initiative—to mitigate first costsassociated with these systems. The existing 1st GEN (First generation)systems suffer from mediocre lifetime battery cycle count and inferiorsystem roundtrip efficiencies resulting in systems that are onlywarranted for 10 years when they are required to match PV systemlifetime of 25 years or longer. Additionally, lack of active, granularbattery management and chronic power conversion inefficiencies, ofexisting systems, can further confront and penalize system owners withsignificant safety concerns and increased lifetime ownership costs.Additionally, regulatory authorities and fire departments are grapplingwith the potential consequences of hazardous fire from non-activelymanaged batteries in the typical battery stack—stationary ormobile—while acknowledging the necessity for BTM storage on thedistribution network for the next-generation grid. Accordingly,financial incentives alone are likely not sufficient to facilitate therequired mass commercial deployment of storage systems on thedistribution networks. Furthermore, without a substantial means ofmonetizing their investments, it is highly unlikely that BTM storage—atpresent pricing—will be adopted and become accepted by the majority ofcustomers on the distribution network irrespective of the presence of PVsystem ownership on their properties. Hence, system affordability,system performance, extension of operational life and, system safetywith a means for their further monetization will remain crucial todriving mass adoption and acceptance.

SUMMARY

In one example, a property power system includes an array ofphotovoltaic (PV) panels. The array of PV panels is configured togenerate DC electrical energy from solar energy radiated toward thearray of PV panels. In some examples, each PV panel of the array of PVpanels includes a first power conversion module to convert between DCelectrical energy and AC electrical energy and to control an operationalcharacteristic of each PV panel. The property power system also includesa group of battery blades configured to store electrical energy. Eachbattery blade of the group of battery blades includes a second powerconversion module to convert between DC electrical energy and ACelectrical energy and to control an operational characteristic of eachbattery blade. The property power system includes a firstsynchronization interface that is configured to aggregate the ACelectrical energy of each of the PV panels. The first synchronizationinterface may additionally control delivery of the AC electrical energyof each of the PV panels to multiple electrical outlets or panels. Thefirst synchronization interface can also implement regulative protectionincluding anti-islanding protection. The property power systemadditionally may include a second synchronization interface configuredto aggregate the AC electrical energy of each of the battery blades, tocontrol delivery of the AC electrical energy of each of the batteryblades, as aggregated, to one or more of an electrical outlet or panel,and implement regulative protection including anti-islanding protection.The property power system also includes a grid circuit disconnectorconfigured to select an islanded mode of operation and to preventback-feed of power during grid outage condition while the array of PVpanels or the group of battery blades is powering an electrical loadcenter in a property that is electrically couplable to the array of PVpanels, the group of battery blades, and a power grid.

In another example, a method of providing property power includinggenerating DC electrical energy from solar energy radiated toward anarray of photovoltaic (PV) panels. Each PV panel of the array of PVpanels includes a first power conversion module to control variousoperational characteristics. The method also includes storing electricalenergy by a group of battery blades. Each battery blade of the group ofbattery blades includes a second power conversion module to controlvarious operational characteristics. The method includes aggregating DCelectrical energy from of each of the PV panels by a first interfacethat performs various operations. Exemplary operations performed by thefirst interface include converting the aggregated DC electrical energyto AC electrical energy, implementing regulative protection includinganti-islanding protection, and controlling delivery of the AC electricalenergy to one or more of an electrical outlet or panel. The method alsoincludes aggregating the electrical energy of each of the battery bladesby a second interface that performs various operations. Exemplaryoperations performed by the second interface include converting theaggregated electrical energy to AC electrical energy, implementingregulative protection including anti-islanding protection, andcontrolling delivery of the AC electrical energy to one or more of anelectrical outlet or panel. The method also includes selecting anislanded mode of operation by a grid circuit disconnector. The methodfurther includes preventing back-feed of power during grid outagecondition while the array of PV panels or the group of battery blades ispowering an electrical load center in a property. In some examples, theproperty is electrically coupled to the array of PV panels, the group ofbattery blades, and a power grid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a chart that illustrates grid network load impacted bysignificant oversupply from variable generation resources according toone aspect of the present disclosure.

FIGS. 2A-2C illustrate various power inversion architectures forPV-battery systems that employ a centralized or string inverter,according to one aspect of the present disclosure.

FIG. 3 illustrates a PV-battery system power inversion architectureusing low voltage AC conversions with inherent vectoral summationaccording to one aspect of the present disclosure.

FIG. 4 depicts various PV-battery system components according to oneaspect of the present disclosure.

FIGS. 5-6 depict a configurable and retrofittable grid circuitdisconnector component according to one aspect of the presentdisclosure.

FIG. 7 is a graph illustrating the reduced cost of the disclosedPV-battery system according to one aspect of the present disclosure.

FIGS. 8-9 depict a load circuit isolator inside the main electric panelfor implementing a grid circuit disconnector component according to oneaspect of the present disclosure.

FIG. 10 depicts grid-circuit disconnector component that can beconfigured and retrofitted, and that includes a portable battery groupaccording to one aspect of the present disclosure.

DETAILED DESCRIPTION

Certain aspects and features in this disclosure are related to aproperty power system that is installed at the property (e.g., behind apower meter). An example of one behind the property power system is asolar powered battery system, which converts solar radiation intoelectrical power and provides electrical power to electrical loadswithin the property. The electrical power from the solar battery systemcan be provided to the main electrical panel at the property. In someapplications, this electrical power can provide the primary source ofpower for the property. In addition, the property power system cansubstitute for the utility grid during grid power outages. In otherwords, the property power system (a behind the meter system) isdownstream to the property owner's electric power meter (e.g., coupledbetween the property and the electric power meter) and, under certainconditions, may remain operational while disconnected from the gridnetwork. While providing power to the property and disconnected from thegrid network, the power production is known as islanded operation (e.g.,the property is on an island with respect to the grid network). Theproperty power system (e.g., a PV-battery system) of the presentdisclosure may be safer and easier to install, operate and utilizerelative to available property power systems. Additionally, the propertypower system enables prevention of back-feed (e.g., power flowing in theopposite direction when disconnected from the grid network) duringislanded operation, provides an interface for controlling the respectivealternating current (AC) output by the PV and battery systems withanti-islanding protection, and optimizes operational parameters of PVpanels and battery cells. In addition, the disclosed PV-battery systemadvantageously combines granular battery management with power inversionin an integrated system.

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols and reference characters typically identify similarcomponents throughout the several views, unless context dictatesotherwise. The illustrative aspects described in the detaileddescription, drawings, and claims are not meant to be limiting. Otheraspects may be utilized, and other changes may be made, withoutdeparting from the scope of the subject matter presented here.

Before explaining the various aspects of the present disclosure indetail, it should be noted that the various aspects disclosed herein arenot limited in their application or use to the details of constructionand arrangement of parts illustrated in the accompanying drawings anddescription. Rather, the disclosed aspects may be positioned orincorporated in other aspects, variations and modifications thereof, andmay be practiced or carried out in various ways. Accordingly, aspectsdisclosed herein are illustrative in nature and are not meant to limitthe scope or application thereof. Furthermore, unless otherwiseindicated, the terms and expressions employed herein have been chosenfor describing the aspects for the convenience of the reader and are notto limit the scope thereof. In addition, it should be understood thatany one or more of the disclosed aspects, expressions of aspects, and/orexamples thereof, can be combined with any one or more of the otherdisclosed aspects, expressions of aspects, and/or examples thereof,without limitation.

In addition, in the following description, it is to be understood thatterms such as front, back, inside, outside, top, bottom and the like arewords of convenience and are not to be construed as limiting terms.Terminology used herein is not meant to be limiting insofar as devicesdescribed herein, or portions thereof, may be attached or utilized inother orientations. The various aspects will be described in more detailwith reference to the drawings.

In various aspects, the disclosed BTM storage system is a PV-batterysystem for distributed generation (DG) or distributed energy resource(DER) such that a property owner may install the system withoutemploying professional help. Property includes buildings, residences,automobiles, other real property and other suitable property. Thedisclosed system may also be installed by professional personnel (e.g.licensed electricians) at a significantly lowered cost due toelimination of system complexity compared to conventional systems. Thedisclosed system is advantageous for several additional reasons,including improved efficient power conversion, granular optimization ofbattery operation and PV panel operation, reduced costs, control ofbidirectional energy transfer, and increased safety. The PV-batterysystem may comprise an enhanced inverter component (EIC), enhanced gridinterface termination box (eGITB), and retrofittable Grid CircuitDisconnector (GCD), which are described in further detail below. Theinverter component may be a suitable inverter such as the SynchronizedInverter Molecule® available from SineWatts, Inc. of Charlotte, N.C.

The eGITB and EIC architecture enables vectoral stacking of individualAC output from each PV panel of a group of PV panels or each batteryblade of a group of battery blades. Each battery blade consists ofmultiple battery cells. Battery blades may also be known as batterystacks or battery banks. In particular, the BTM system can comprise oneor more strings, in which each string comprises a plurality of stringmembers that each includes a voltage source and inverter component. Theinverter component may be the EIC, which is a bi-directional low voltageinverter capable of individually converting the DC voltage of each PVpanel or battery blade into its respective AC output. These individualAC outputs may inherently be vectorally summed into a single combined ACoutput. Accordingly, a PV panel string and a battery blade string areeach connected to their corresponding eGITB and provide their respectiveconsolidated AC output to the corresponding eGITB. One benefit of thisarchitecture is that each dedicated EIC (corresponding to each stringmember) optimizes each string member. In other words, for each PV panelstring member of the PV panel string, the corresponding dedicated EICmay achieve maximum power point tracking (MPPT) and rapid shutdown(e.g., based on fault detection or emergency crew instigated electricservice interruptions). In addition, for each battery blade stringmember of the battery blade string, the corresponding dedicated EIC mayachieve individualized battery blade charge-discharge management andactive charge balancing among the group of battery blades.

In this way, the system architecture inherently combines granularbattery management with the power inversion process. Additionally, dueto the architecture, the battery operation optimization can beindependent of the PV panel operation optimization. Vectoral summationallows this PV-battery system to advantageously obviate the need for ahigh voltage intermediate DC bus and enables the use of identicalhardware for both the PV and battery subsystems. Nonetheless, differenthardware may be used under suitable circumstances. In the disclosedAC-stacking architecture, the vectoral summation of the low voltage EICsresults in a consolidated AC output that is provided to the eGITB. Tothis end, the PV panel string and a battery blade string may each have acorresponding eGITB. The eGITB may comprise a mechanism for allowing andsafeguarding unidirectional and bidirectional power flow to the PVpanels and battery blades, respectively. In particular, the eGITB mayimprove the safety of the system by implementing an anti-islandingalgorithm and back-feed prevention, as described in further detailbelow.

The eGITB and EIC architecture may increase power conversion efficiency.The disclosed PV-battery system may also equitably distribute theelectrical load of the subject property where the system is installedsuch that battery life is extended. In addition, the system can enhancedispatching of the available power capacity at the property by gridoperators to address the disparity between forecasted load andelectrical generation by the local utility. For example, the batteryblades may store the increased energy generated during the middle of aday when energy unit rates (measurable in kilowatt hours (kWh)) areexpected to be low due to lower demand (load) and excess generation, asdiscussed with reference to FIG. 1. Similarly, the battery blades maysupply the stored energy to meet higher demand (load) in the evening andearly nighttime hours when energy unit rates are expected to be higher,also as discussed with reference to FIG. 1. The battery blades can belocated in a separate portion of the property than the PV panels.

Another aspect of the invention will enhance the benefit for the systemowner by utilizing the rate differential, as described above, whileserving and fulfilling the grid requirements of maintaining load versusgeneration equilibrium at the distribution network. Additionally, theseindividual systems may be aggregated by system aggregators, DERmanagement system (DERMS) operators, grid operators or the competentauthority for excess available capacity and supply the bulk powerrequirements of Regional Transmission Organizations (RTOs) andIndependent System Operators (ISOs). The inclusion of the GCD enablesproperty owners to operate DG resources or DER (e.g., PV panels and/orbattery blades) in an islanded mode or off-grid or grid-disconnectedmode. Importantly, the GCD implements back-feed prevention when the PVpanel or battery blade is operated in an islanded mode. That is, the GCDprevents electricity from flowing back through the property's maincircuit breaker to the corresponding power grid, such as the power gridof the local power utility. The GCD may comprise a controller fordetecting an outage at the power grid or when the grid voltage orfrequency has violated their thresholds per applicable regulations. Insuch detected circumstances, an islanded mode of operation may beappropriate. Thus, even in power grid outage situations, the propertyowner may safely utilize the energy provided by the PV panels and/orbattery blades for the loads in the property. The property owner couldalso predesignate only certain load circuits in the property to receivepower from the DER, which may further promote optimum usage of on-siteenergy resources in an off-grid mode. The GCD may also be utilized inDER systems comprising of other types of generation resources (e.g. fuelcell generators, microturbines and such) and other types of storageresources (compressed air energy storage (CAES), liquid air energystorage (LAES), flywheel energy storage and such).

FIG. 1 is a chart 100 illustrating the evolution, over the years, of theintraday variations of electric load on their network for a typicalspring day. As the utilization of PV for electrical generationincreases, customer-sited generation also increases, thereby reducingdemand during the middle of the day when solar insolation is typicallyabundant. However, as the day progresses, with reducing solarinsolation, the demand increases rapidly during the sunset hours. Thex-axis of the graph indicates the time during a day while the y-axis ofthe graph indicates the amount of load as measured in megawatts (MW).The existing centralized electric grid was not designed to handle rapiddemand fluctuations due to over and under supply from variablegeneration resources. As illustrated by the chart, the risk ofovergeneration is predicted to increase as PV becomes more prolific. Theissues of overgeneration risk and steep ramping needs, as portrayed bythe graph, may be addressed by the improved BTM system of the presentdisclosure. FIG. 1 illustrates various year's corresponding to each linealong the chart. For instance, line 108 corresponds to a usage chart for2019, line 114 corresponds to a usage chart for 2018, line 116corresponds to a usage chart for 2017, line 118 corresponds to a usagechart for 2016, line 120 corresponds to a usage chart for 2015, line 122corresponds to a usage chart for 2014, line 124 corresponds to a usagechart for 2013, and line 126 corresponds to a usage chart for 2012. Aparticular point of interest in the chart is the 3-hour ramp depicted byportion 110. A forecast usage point for 2020 corresponds to estimatedpoint 112.

FIGS. 2A-2C illustrate various power inversion architectures forPV-battery systems according to various aspects of the presentdisclosure. FIGS. 2A-2B show conventional high voltage power inversionarchitectures that employ a centralized or string inverter. TheDC-coupling architecture 200 of FIG. 2A uses a DC step-up converter 206to step up the voltage of the battery bank 204 to match that of theinverter's internal DC-voltage bus. This internal DC voltage level istypically set by the connection requirements to the AC-grid 209. TheDC-coupled PV array 202 is also required to adhere to this voltage busrequirement by the inverter circuitry. In particular, the DC step-upconverter 206 may convert low voltage such as 48 volts (V) to highvoltage such as 500V, 700V or 900V. A central inverter 208 is used toconvert the input high voltage DC to output high voltage grid AC. Theconversions may realize losses. For example, the DC step-up conversionmay have a one-way efficiency of 97% or lower while the centralizedpower inversion may have a one-way efficiency of 98% or lower. The ACbattery architecture 210 of FIG. 2B operates similarly as that of FIG.2A, with the operation illustrated by inclusion of the PV array 212,battery bank 214, DC step-up converter 216, central inverter 218 in theAC battery of FIG. 2B, and AC output 219. Accordingly, a typical 95% orlower one-way efficiency may be realized for the architectures of FIGS.2A-2B. Accounting for both the charging and discharging operations,conventional architectures such as those of FIGS. 2A-2B may realizeroundtrip efficiencies in an approximate range of 86% to 90%. FIG. 2Cshows a power conversion architecture 220 that utilizes a centralinverter 228 and modular DC-optimizers 226A-226E for maximum power pointtracking (MPPT) operation of the PV panels 222A-222E and modularDC-optimizers 227A-227E for charge balancing of the battery blades224A-224E collectively, in the “battery bank 224”. Consequently, theseparate DC step-up operation is eliminated in FIG. 2C. A modularDC-optimizer 226A-226E may be used for each PV panel 222A-222E,collectively “PV array 222” and for each battery blade 224A-224E in thebattery bank 224 (i.e., a group of battery blades). The PV panels222A-222E and battery blades 224A-224E may be arranged in series,parallel, or a combination of both, respectively. FIG. 2C shows a seriesof modular DC-optimizers (226A-226E and 227A-227E) forming a highvoltage DC bus. A central inverter 228 (e.g., a string inverter) thenconverts the string DC flowing through the high voltage DC bus. Theproperty power system may include a grid circuit disconnector (GCD) 232between the inverter 228 and utility grid 229 to accommodate bothon-grid and off-grid (islanded) modes of operation and serve theproperty electrical loads 234. Based on the DC-optimizer operationoccurring at an estimated 99% conversion efficiency and the centralinversion occurring at an estimated 98% or lower efficiency, the powerconversion architecture 220 of FIG. 2C realizes an estimated one-waysystem efficiency of 96% to 97% and an estimated roundtrip systemefficiency of 92% to 94%. While a GCD is only depicted in FIG. 2C, itwill be appreciated that a GCD can be included in FIGS. 2A-2B.

FIG. 3 illustrates a PV-battery system power inversion architectureusing low voltage AC conversions with inherent vectoral summation,according to various aspects of the present disclosure. The disclosedBTM architecture 300 combines high power conversion efficiency withgranular battery and PV management. As shown in FIG. 3, a PV-modulestring 302 comprises a series of PV panel string members 302A-302E thateach has a corresponding bi-directional granular inverter 306A-306E(e.g., EIC). Similarly, a battery blade string 304 comprises a series ofbattery blade string members 304A-304E that each has a corresponding EIC307A-307E. Any appropriate number, as determined by systemcharacteristics such as the grid voltage level and requirements, as wellas the individual voltage source level and variability (PV or batteryblade); of string members can be employed. Accordingly, FIG. 3 portraystwo separate strings, although any number of strings could be engaged aspermissible by the architecture, hardware, and equipment power rating.Thus, the system will allow multiple PV strings or multiple batteryblade strings connected to their respective eGITB (e.g., PV eGITB 308and battery eGITB 309). FIG. 3 also includes a GCD 311 coupled to eachof the respective eGITBs and the utility grid 310 to accommodate bothon-grid and off-grid (islanded) modes of operation and serve theproperty electrical loads 312.

Alternatively, each string member may comprise one or more PV panels andone or more battery blades combined into one generation-storage voltagesource (GSVS). An appropriately configured EIC connected to each GSVScan then be utilized to manage and optimize both its PV panel(s) andbattery blade(s). In some examples, the battery blades 304A-304E arestacked inside an enclosure and installed in the interior of a property(e.g., a garage of a residence, a utility room of a commercialbuilding), although the battery blades 304A-304E may be installed in anysuitable location including being co-located with the PV panels302A-302E. The EICs (PV EICs 306A-306E or battery bank EICs 307A-307E)and eGITB (PV eGITB 308 or battery bank eGITB 309) may also be used withbattery blades in other suitable applications besides real property. Forexample, the EICs and eGITB can be used to manage the charging anddischarging of battery blades or battery stacks inside an electricvehicle (EV), hybrid electric vehicle (HEV) or plug-in hybrid electric(PHEV) vehicle. The battery stacks and their corresponding EICs may behoused inside the battery enclosure of the EV, HEV or PHEV. Thecorresponding eGITB may also be an integral part of the vehicle or mayalso be installed in a portion of the property (e.g., the garage orsomewhere convenient in the property). The corresponding eGITB cancharge the battery stacks while implementing active battery managementas described above. The output of the respective eGITBs 308 and 309 isAC output and may be connected to the utility grid 310.

Furthermore, the eGITB may supply energy back to the grid in a vehicleto grid (V2G) mode. The array of PV panels may be installed outside,such as on the rooftop of the property or at any other location suitablefor the application. The EICs enable granular, high efficiency lowvoltage DC to AC conversions with inherent vectoral summation.

The presently disclosed architecture does not require a high voltageintermediate DC bus, thus eliminating any DC wiring as reflected in theDC-coupled architectures shown in FIGS. 2A and 2B. It relies solely onthe property's existing AC-wiring, thereby, improving safety of thesystem due to the inherent benefits of an AC-system. This may alsoreduce the cost and improve the efficiency of the system. Instead of thehigh voltage DC bus, the plurality of low voltage AC output by thestring members are inherently aggregated without the requirement of anycontrol communications and provided to the corresponding eGITB (i.e, PVeGITB 308 or battery bank eGITB 309). The eGITB (i.e., PV eGITB 308 orbattery bank eGITB 309) is a disconnection mechanism, string protectionand grid-to-string synchronization unit (e.g., a synchronizationinterface) comprising electrical, electronic, and electromechanicalcomponents. The eGITB aggregates the plurality of output AC so that theeGITB may act as a voltage source for the property. For example, theeGITB may provide 120V, 240V or some other appropriate voltage in asingle or polyphase configuration. While only 240V single phase isdepicted in FIG. 3, it should be appreciated that other grid voltagessuch as 208V, 480V 3-phase, and other known grid voltages may also beused. To this end, the eGITB can be plugged into 120V or 240V outletsincorporated into a wall of the property. The eGITB may also have acontroller configured to supply control signal(s), over wired orwireless connection, to the string members (individually or as a group)to dynamically control the low voltage power AC inversion or DCconversion. Specifically, in some situations, it may be desirable toimplement a simplified DC architecture so that the string members outputDC that is inherently aggregated and provided to the corresponding eGITBconfigured to operate in DC-mode. For synthesizing a DC output—a scalarquantity—at the corresponding eGITB, synchronization of the stringmembers is not a necessity. However, each of the individual EICs willneed to be configured for DC output. Accordingly, the architecture andthe same hardware may be adapted to handle both AC output and DC outputat the EIC and eGITB. An EIC/eGITB string configured for DC output willrequire an additional DC-AC inverter to connect to the electric grid. AneGITB configured for DC output may be part of the AC/DC inverterhardware and accordingly, reside in the same inverter enclosure. Forexample, the eGITB could set a voltage or current characteristic of theinversion to achieve a desired power or current in grid-tie mode anddesired power or voltage in off-grid mode. More generally, the eGITB cancontrol the power factor of the system, protect the battery blades, andPV panels based on fault diagnosis and detection (e.g., using keyperformance indicators and degradation profile), account for variationsin environmental conditions, and adjust operational field quantities(voltage, current) of the battery blades and PV panels. Furthermore, theeGITB may allow and control the bi-directional power flow for storingenergy and supplying power to electrical loads. The eGITB also canimplement anti-islanding protection, which can be determined by asuitable islanding detection method (e.g., determining that a change incommand frequency is consistently positive or negative and determiningwhether the change in command frequency is within a threshold band) suchas that described in U.S. Pat. Nos. 9,997,920 and 10,069,304.

FIG. 4 depicts various PV-battery system components according to variousaspects of the present disclosure. Specifically, the EIC, eGITB, and GCDare shown in the context of a residential property 400, such as a house.As can be seen in FIG. 4, the PV panel array (i.e., including panelarrays 421A-421C) is installed in the house rooftop while the batteryblades (432A-432C) are housed in a house enclosure. Each PV panel of thePV panel array 421A-421C has a corresponding EIC 424A-424C and junctionbox 422A-422C. In an alternate arrangement, the functionalities of thejunction box 422A-422C may be fully accommodated by the EIC 424A-424C toeliminate the junction box from the PV panel. Each battery blade432A-432C has a corresponding EIC 434A-434C. The PV panel array(421A-421C) and the group of battery blades (432A-432C) each may provide240V in AC output (e.g., PV AC output 436A or battery blade AC output436B) from their respective eGITB (i.e., PV panel array eGITB 420 orbattery blade eGITB 430) to the main electric panel (which includes themain circuit breaker 408) or the load center of the house. In this way,the DER (PV-battery system) resources may be used for the power demandsof the house before power from the local utility power grid is consumed(as tracked and indicated by the associated electric meter 406 shown inFIG. 4). The GCD 412 (illustrated inside the Smart Main Panel 410) shownin FIG. 4 also enables operating the PV-battery system in an islandedmode. As discussed above, an islanding condition such as when the localutility power grid experiences a power outage can be detected using asuitable islanding detection method. Thus, when the GCD 412 and theconnected eGITBs (i.e., PV panel array eGTIB 420 or battery blade eGITB430) detect a grid outage condition, the GCD 412 may be disconnected ordisengaged to isolate the rest of the load center from the house's maincircuit breaker 408 (MCB). Various embodiments of the GCD 412 areachieved as disclosed in FIGS. 5-6 and FIGS. 8-9. Consequently, the GCD412 may allow the house or the property to be electrically serving itsloads from the PV panel array 421A-421C and/or battery blades 432A-432Cwhile the house remain disconnected from the local utility power grid402. In other words, the GCD 412 disconnects the house from the localutility power grid (e.g., first portion of utility grid 402 or secondportion of utility grid 404). to prevent back-feed from the DER duringislanded mode of operation. In addition, the GCD 412 may comprisecircuitry for synchronization, communications and telemetry in both thegrid-connected and off-grid mode of operations. For example, the GCD 412circuitry can be used to communicate with the competent power gridauthority and respond to grid operator and/or system aggregator signalsfor increasing or decreasing active and reactive load of the property,in response to real-time grid requirements. The GCD 412 may also adjustbuilding active and reactive loads (e.g., 240V load 440) based onlearning customer and/or building occupants' energy usage and dynamicload profile to maximize benefits for the owner by serving instantaneousgrid support and fulfilling pre-assigned or on-demand capacity dispatchrequirements. Accordingly, the GCD 412 may allow a single point ofaccess for the competent authorities to access, control, monitor theseindividual DER systems to verify, meter and settle energy transactionsfor grid support and advanced grid operations and fulfill therequirements of a DER management system (DERMS). As used in thisdisclosure, grid-connected, grid-tie, or grid-interactive mode may referto operation of the system at the property when connected to theexternal grid network for regular utility grid mode, microgrid mode orlocal neighborhood nanogrid mode.

FIGS. 5-6 depict an embodiment of the GCD 509 that is retrofittable forexisting residential main electric panels and may be configured to allowselective loads of the house be served during a grid outage according tovarious aspects of the present disclosure. In FIG. 5, the GCD isimplemented as configurable branch circuit adapters, cBCA 506,comprising switched disconnectors 507 and branch circuit isolators 510for islanded operation. New wiring is built into the configurable branchcircuit adapters, cBCA 506, and selectively employing switcheddisconnectors 507 and branch circuit isolators 510 may serve the owner'sload requirements. The branch circuit isolators 510 may be easilyinstalled in an electric panel (which typically includes the maincircuit breaker 508) by the property owner. In this way, the propertyowner may predetermine and selectively choose critical load circuits inthe home that are served during islanded operation. Other non-criticalload circuit breakers will be adapted with a circuit breaker isolator510 which may be configured to isolate on both sides of theadapter—grid-side and load-side, such that the non-critical load circuitbreaker is completely isolated and electrically floating when inislanded mode of operation and remain connected when in grid-tie modeoperation, thereby, allowing the non-critical loads to operate ingrid-tie mode only. To this end, the property owner may install switcheddisconnectors 507 for those load circuits that the owner desires toderive power from, during islanded operation, such as the circuits towhich the eGITBs (of the PV array 521A-521C and/or the group of batteryblades 532A-532B) may be connected. Additionally, circuit breakerisolators 510 may include branch circuit isolators that may be installedfor those loads that the owner desires to power during islanded oroff-grid operation and configured for isolation on the grid-side only.The combination of the adapters for switched disconnectors 507 andbranch circuit isolators 510 implements a GCD 509 that is retrofittable.Normal load circuits will remain energized during grid-tie modeoperation and will be disconnected, by design, during grid outage oroff-grid or islanded operation. Thus, the cBCA 506 of FIG. 5 isconfigurable by the homeowner and enables further flexibility inmanaging and customizing the various load circuits. This may result inreduced electrical consumption and consequently preserve energyresources as well as reduce waste. In particular, this may extend thelife of battery blades 532A-532C and/or optimize which loads in thehouse receive power. FIG. 5 also depicts that each PV panel of the PVpanel array 521A-521C has a corresponding EIC 524A-524C and junction box522A-522C, each battery blade 532A-532C has a corresponding EIC534A-534C, and the grid circuit has a first portion 502 and secondportion 504, and an electric meter 506. Each of the PV panel array521A-521C and the battery blades 532A-532C can have a respective PVeGITB 520 and a battery bank eGITB 530, further coupled to PV AC output536A and battery bank AC output 536B.

FIG. 6 shows one aspect of the circuit breaker adapters with in-builtisolator or switched disconnect and monitoring circuitry. Such in-builtbypass wiring in the adapters may accomplish the circuit modificationfor DER islanded mode operation with only minimal involvement of theproperty owner. This circuit modification may leave the remainder of themain panel and home system configured for normal grid-tie modeoperation. For example, FIG. 6 illustrates a circuit breaker mounting601 inside a main panel 600. A circuit breaker 606 may be coupled to theneutral bar 602 and bus bar 604. FIG. 6 also illustrates a side view ofmain panel 610 including a circuit breaker 616, neutral bars 611 and 612and bus bar 614. FIG. 6 further illustrates a circuit breaker mountinginside a main panel 620 including a circuit breaker 630, a circuitbreaker adapter 628, and neutral bars 621 and 622, bus bar 624 andbypass-wiring 626 for islanded mode operation.

FIG. 7 is a graph 700 illustrating the reduced cost of the disclosedPV-battery system according to various aspects of the presentdisclosure. All cost breakdowns are normalized to that of the medianreported cost (e.g., the vertical axis normalized at 1.0) of installingconventional DC-coupled (FIG. 2A) or AC-battery systems (FIG. 2B). FIG.7 illustrates a cost and savings of the disclosed stationary batterysystem of FIG. 3 compared with conventional systems that lack thedisclosed features. For example, the conventional system requiresvarious costs including: exemplary cost 706 (e.g., batteries, enclosure,and inverter), exemplary cost 710 (e.g., ancillary hardware), exemplarycost 712 (e.g., professional installation), exemplary cost 714 (e.g.,auto-transfer switches (ATS)), exemplary cost 716 (e.g., install ATS). Asummation of each of these exemplary costs produces the median reportedcost 704. In comparison, the system of FIG. 3 including featuresdisclosed herein are able to recognize various cost improvements. Forinstance, a system as disclosed herein, benefits from exemplary costimprovement 718 (built-in ATS, no install required), exemplary costimprovement 720 (built-in ATS, no separate hardware required), exemplarycost improvement 722 (wall-plugged, self-installed), exemplary costimprovement 724 (all-inclusive hardware package), exemplary costimprovement 726 (includes a battery and inverter as a complete set). Thesummation of the exemplary cost savings results in the cost 708(including component cost 709) of the disclosed system as disclosedherein. The difference between the cost 708 and the median cost 704(including component cost 707) represents the savings improvement of thedisclosed system over the conventional median system.

FIGS. 8-9 depict a further circuit implementation of a grid circuitdisconnector 809 (GCD) component according to various aspects of thepresent disclosure. In particular, FIGS. 8-9 depict a form of the GCD809 shown in FIG. 4. The aspect of GCD shown in FIGS. 8-9 may bereferred to as a load circuit isolator 810 (LCI). As shown in FIG. 8,the LCI 810 disconnects the entire building load center 812 from themain circuit breaker 808 (MCB) during a grid outage thereby achievingback-feed prevention to the grid network (e.g., a first grid networkportion 802 and a second grid network portion 804) and serving all loadsin the property with the resident PV panel array (821A-821C) and batteryblades (832A-832C) system. FIG. 8 illustrates various other circuitcomponents as described herein. For instance, FIG. 8 illustrates PVeGITB 820 and battery bank eGITB 830, PV AC output 836A, battery groupAC output 836B, and electric meter 806. FIG. 8 also depicts that each PVpanel of the PV panel array 821A-821C has a corresponding EIC 824A-824Cand junction box 822A-822C, each battery blade 832A-832C has acorresponding EIC 834A-834C, and the grid circuit has a first gridnetwork portion 802 and second grid network portion 804, and an electricmeter 806.

FIG. 9 illustrates a ganging mechanism 900 that can be utilized by allembodiments of GCD (shown in FIGS. 5-6 and FIGS. 8-9, respectively) todisconnect all generating load circuits and their corresponding circuitbreakers. As shown in FIG. 9, disengagement of the MCB 902, such as byphysically turning-off the arm of the circuit breaker, causes the gangedcircuit breakers 908 to disconnect. This causes all generating circuits,such as those connected to the eGITBs for the PV and battery systems, tobe disconnected from the load center. The eGITBs may also electricallydisconnect from their respective load circuit breakers upon detection ofa low voltage at their electric outlet or output terminals. In this way,multiple layers of disconnection may be used to increase the safety ofdisclosed system. Specifically, emergency service personnel, such asfirefighters, can disengage the MCB 902 along with the other generatingcircuits (that are ganged to the MCB) and attend to any emergencieswithout the threat of any energized or live electrical systems in thehouse. While a mechanical ganging mechanism is depicted in FIG. 9,various other ganging techniques may be employed, for deactivation ofthe DER circuit breakers. The techniques may involve detection (opticalor otherwise) of the MCB switch arm in the OFF-position. While twospecific aspects of the GCD have been described above, other suitableaspects may be derived from the disclosed examples of the GCD, whetherin isolation or in combination. FIG. 9 also depicts a utility feed 914coupled to the MCB 902 at junction point 904 and the supply mains 910coupled to the bus bars 906. Additionally, FIG. 9 illustrates the busbars 906 coupled to a LCI 912. The LCI 912 is described previouslyherein.

FIG. 10 depicts a configurable and retrofittable grid circuitdisconnector component including a portable battery group 1042A-1042Caccording to one aspect of the present disclosure. The portable batterygroup 1042A-1042C can be used with any aspect of FIGS. 1-9. As can beseen in FIG. 10 and as described with regard to FIGS. 4-5, the PV panelarray (i.e., including panel arrays 1021A-1021C) is installed in thehouse rooftop while the portable battery group (1042A-1042C) is housedin the vehicle 1040 or other type of automobile. Each PV panel of the PVpanel array 1021A-1021C has a corresponding EIC 1024A-1024C and junctionbox 1022A-1022C. In an alternate arrangement, the functionalities of thejunction box 1022A-1022C may be fully accommodated by the EIC1024A-1024C, thereby eliminating the junction box from the PV panel.Each battery blade (e.g., battery blade 1042A) in portable battery group1042A-1042C has a corresponding EIC. The PV panel array (1021A-1021C) orthe group of battery blades (1042A-1042C) each may provide 240V in ACoutput (e.g., PV AC output 1036A or portable battery group AC output1036B) from an eGITB (i.e., PV panel array eGITB 1020 or portablebattery group eGITB 1048) to the main electric panel or the load centerof the house. In this way, the vehicle 1040 and/or the PV panel array1021A-1021C may provide power to the property. The vehicle 1040 includespower adapter module 1044, and conductors 1046A-1046B. The propertyincludes an electrical meter 1006, an electric panel 1009, a maincircuit breaker 1008, and GCD 1007.

For example, a property power system includes an array of photovoltaic(PV) panels and a portable battery group. Each PV panel in the array isconfigured to generate DC electrical energy from solar energy radiatedtoward the array of PV panels. In some examples, each PV panel of thearray of PV panels is coupled to a first synchronized, non-isolated(transformerless in the path of power flow) power conversion module toconvert between DC electrical energy and AC electrical energy, targetingan operational characteristic of each PV panel to control delivery ofthe AC electrical energy of each of the PV panels. The property powersystem includes a first non-isolated synchronization interface that isconfigured to aggregate the AC electrical energy of each of the PVpanels. The property power system also includes a portable battery group(e.g., battery blades installed in a vehicle) configured to deliver andstore electrical energy. Each battery blade of the portable batterygroup is coupled to a second synchronized, non-isolated power conversionmodule to convert between DC electrical energy and AC electrical energytargeting an operational characteristic to control delivery and storageof the AC electrical energy of each of the battery blades. The firstnon-isolated synchronization interface may additionally control deliveryof the AC electrical energy resulting from the array of PV panels to oneor more of an electrical outlet or the main electric panel on theproperty. The property power system additionally may include a secondnon-isolated synchronization interface to control delivery and storageof the AC electrical energy resulting from the group of battery bladesto one or more of an electrical outlet or the main electric panel on theproperty. The property power system also includes a grid circuitdisconnector configured to select an islanded mode of operation (ordisconnected from the utility grid) and to prevent back-feed of powerduring grid outage condition while the electrical load center (or themain electric panel) on the property remain energized (powered) by thearray of PV panels and/or the portable battery group.

While various details have been set forth in the foregoing description,it will be appreciated that the various aspects of the system and methodfor providing a property power system behind the meter may be practicedwithout these specific details. One skilled in the art will recognizethat the herein described components (e.g., operations), devices,objects, and the discussion accompanying them are used as examples forthe sake of conceptual clarity and that various configurationmodifications are contemplated. Consequently, as used herein, thespecific exemplars set forth and the accompanying discussion areintended to be representative of their more general classes. In general,use of any specific exemplar is intended to be representative of itsclass, and the non-inclusion of specific components (e.g., operations),devices, and objects should not be taken as limiting.

Unless specifically stated otherwise as apparent from the foregoingdisclosure, it is appreciated that, throughout the foregoing disclosure,discussions using terms such as “processing” or “computing” or“calculating” or “determining” or “displaying” or the like, refer to theaction and processes of a computer system, or similar electroniccomputing device, that manipulates and transforms data represented asphysical (electronic) quantities within the computer system's registersand memories into other data similarly represented as physicalquantities within the computer system memories or registers or othersuch information storage, transmission or display devices.

In a general sense, those skilled in the art will recognize that thevarious aspects described herein which can be implemented, individuallyand/or collectively, by a wide range of hardware, software, firmware, orany combination thereof can be viewed as being composed of various typesof “electrical circuitry.” Consequently, as used herein “electricalcircuitry” includes, but is not limited to, electrical circuitry havingat least one discrete electrical circuit, electrical circuitry having atleast one integrated circuit, electrical circuitry having at least oneapplication specific integrated circuit, electrical circuitry forming ageneral purpose computing device configured by a computer program (e.g.,a general purpose computer configured by a computer program which atleast partially carries out processes and/or devices described herein,or a microprocessor configured by a computer program which at leastpartially carries out processes and/or devices described herein),electrical circuitry forming a memory device (e.g., forms of randomaccess memory), and/or electrical circuitry forming a communicationsdevice (e.g., a modem, communications switch, or optical-electricalequipment). One having skill in the art will recognize that the subjectmatter described herein may be implemented in an analog or digitalfashion or some combination thereof.

In other instances, one or more components may be referred to herein as“configured to,” “configurable to,” “operable/operative to,”“adapted/adaptable,” “able to,” “conformable/conformed to,” etc. Thoseskilled in the art will recognize that “configured to” can generallyencompass active-state components and/or inactive-state componentsand/or standby-state components, unless context requires otherwise.

In certain cases, use of a system or method may occur in a territoryeven if components are located outside the territory. For example, in adistributed computing context, use of a distributed computing system mayoccur in a territory even though parts of the system may be locatedoutside of the territory (e.g., relay, server, processor, signal-bearingmedium, transmitting computer, receiving computer, etc. located outsidethe territory).

What is claimed is:
 1. A system for distributing, storing, and generating energy, the system comprising: an array of photovoltaic (PV) panels configured to generate DC electrical energy from solar energy radiated toward the array of PV panels, wherein each PV panel of the array comprises a first power conversion module to convert between DC electrical energy and AC electrical energy and to control an operational characteristic of the PV panel; a group of battery blades configured to store electrical energy, wherein each battery blade of the group of battery blades comprises a second power conversion module to convert between DC electrical energy and AC electrical energy and to perform charge balancing among the battery blades of the group of battery blades; a first synchronization interface configured to aggregate the AC electrical energy of each of the PV panels, to control delivery of the AC electrical energy of each of the PV panels, as aggregated, to one or more of an electrical outlet or panel, and to implement anti-islanding protection; a second synchronization interface configured to allow and control bidirectional power flow for storing energy and supplying power to electrical loads and aggregate the AC electrical energy of each of the battery blades, to control delivery of the AC electrical energy of each of the battery blades, as aggregated, to one or more of an electrical outlet or panel, and to implement anti-islanding protection, wherein the second synchronization interface includes a controller configured to adjust operational field quantities of the battery blades to control the charge balancing; and a grid circuit disconnector that includes a controller configured to select an islanded mode of operation and to prevent back-feed of power during a grid-outage condition while one or more of the array of PV panels and the group of battery blades is powering an electrical load center in a property that is electrically couplable to the array of PV panels, to the group of battery blades, and to a power grid.
 2. The system of claim 1, wherein the grid circuit disconnector comprises a communication circuit configured to communicate with the power grid to respond to power grid signals to change one or more of an active and a reactive load of the property.
 3. The system of claim 2, wherein the grid circuit disconnector is further configured to adjust active and reactive loads of the property based on learning an energy usage and dynamic load profile of the property.
 4. The system of claim 2, wherein the grid circuit disconnector defines a point of access that is accessible to control the system and to perform a grid operation.
 5. The system of claim 1, wherein the property is a vehicle, and wherein the group of battery blades and each of the second power conversion modules reside within the vehicle, and wherein the second synchronization interface resides inside or outside the vehicle.
 6. The system of claim 1, wherein the property comprises a main circuit breaker coupled via a ganging mechanism to a plurality of generating load circuit breakers. 